Anyone know anything about motors (Electric ones)

[Link]

I'm considering trying to construct a pair of electric motor powered roller blades, as my commute to work is about to shorten to 2 miles, and I don't know how to figure out how powerful a motor I need.

For example, I know how to calculate speed - for example if I use one of these motors (N98BN) on a 1:1 ratio at 15 volts (http://www.maplin.co.uk/Module.aspx?ModuleNo=43368) it will go at roughly 20 mph (Just an example, I don't intend to make them that fast) but I have no idea how to figure out how much weight they would be able to push. Can it be calculated from the torque figure? If so, can anyone provide the formula?

 

[Dekstar]

Sorry I don't know anything about motors, but that sounds like a very complicated project. Keep us updated with pics and stuff once you get started, because it sounds awesome.

 

[CptStern]

just buy these:

I'm not famliar with eletric motors but for the love of god please get someone to film your maiden voyage. a few cameras at different angles would be nice ..so that we can capture the moment you slam into the side of a mountain/fall off a cliff

 

[Dan]

rolling torque will depend on a lot of variables. What you want to know is how much force will it take to push your forward on your roller blades. Once you know how much force you need you can directly convert that to torque using the diameter of your wheel.

Force will depend on slope, wind resistance, rolling resistance. In general the drag force will increase exponentially with velocity. Based on typical bicycle rider power output at least 100 watts is necessary to get a modest speed. At 2 meters per second, 100 watts translates to 50 newtons. Add a bit of fudge factor and say you need 100 N of force. If you wheels are 4 cm in diameter that's 2 newton metres of torque. In common units that's about 1.5 foot pounds of torque as a ballpark figure. You will need a lot more if you want to go up hills though.

 

[Ridge]

Electric motors

How the **** to they work?

 

[Raziaar]

Design your skates to be like those little toy cars that you drag back with a lot of force, and then they race forward.

Just hitch yourself behind a car for a couple blocks and then zoom your way to work!